Charged Higgs boson withmH<mB?

Abstract

We argue that the existence of charged Higgs bosons with $m_{\mathrm{Higgs}}<m_B$ is subject to severe constraints from $B$ decays. Our analysis is performed using a model (involving a Higgs triplet) with a pseudo-Goldstone charged Higgs boson whose mass is predicted to be 3.5 GeV, with phenomenological remarks about charged Higgs bosons in general. Although allowed by present experimental limits, this model could be ruled out by attainable limits from $B$ decays.